Most Notorious Weed Trees Out There: The Best Guide to Identifying and Eliminating Them

Dandelions and couchgrass are often the first weeds that come to mind when we think of weeds. Even so, it’s surprising that trees can also be weeds! These trees can cause havoc in your backyard, as well as the surrounding environment. This article will help you identify and eliminate the 10 most weedy trees.

What Trees Are Considered Weeds in the USA?

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Trees can be considered weeds if they spread seeds quickly and compete with other species. Even native Australian species can become a nuisance if they invade foreign areas.

Early identification of these “weed trees”, prevents garden invasion and environmental disruption.

Tree Type	Tree Features
Norway Maple	Colorful autumn leaves, invasive, rapid growth.
European Olive	Olives are edible when invading.
Tree of Heaven	Fast-growing, invasive, pungent odor.
Black Locust	Invasive wood that fixes nitrogen.
Yellow Bells	Pollinators are attracted to invasive, drought-tolerant plants.
Camphor Laurel	Camphor invasive source.
Chinese Celtis	Invasive, drought-tolerant.
Mysore Thorn	Invasive, drought-tolerant.
Cockspur Coral Tree	Red flowers that are invasive and attractive.
Golden Wreath Wattle	Yellow flowers.

Ten Most Common Weed Trees Out There

Here is a brief exploration of the 10 most common trees, which, although they may surprise, are often classified by weeds because of their rapid spread and invasive growth pattern.

1. Norway Maple
2. European Olive
3. Tree of Heaven
4. Black Locust
5. Yellow Bells
6. Camphor Laurel
7. Chinese Celtis
8. Mysore Thorn
9. Cockspur Coral Tree
10. Golden Wreath Wattle

1. Norway Maple (Acer Platanoides)

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Norway Maple (Acer platnoides) is an invasive, beautiful tree that was originally from Norway. It’s often used as a park or street tree. The rapid growth of the Norway Maple and its adaptability are what make it invasive.

It can outpace all other plants and create a thick canopy. It also absorbs nutrients and destroys the understory vegetation.

Look for large, dark-green leaves that turn yellow during the autumn, plumper, cherry-brown buds during the winter and a white bead when you pull the stem of the leaf.

This tree must be completely removed, including its seeds, to prevent a regrowth.

Plant Type	Tree
Plant Size	Up to 98 feet tall
Flower Size	Small
Flower Timing	Late Spring
Flower Color	Yellow-green
Leaf Color	Dark green turns yellow as the leaves fall
Leaf Shape	Broad-lobed
Growth Rate	Fast
Temperature Requirements	Adaptable to changing conditions
Invasive	Yes

2. European Olive (Olea Europaea)

Image by and Credit to: Forest and Kim Starr

Due to its invasiveness, the European Olive (Olea Europaea) has been deemed an invasive tree. It takes up a lot of space in different ecosystems, and it contributes to the destruction of forests and riparian zones.

It is easily recognized by its silvery-gray leaves and small yellow flowers.

Controlling the growth of woody plants requires either a complete plant removal down to the roots or the application of herbicides.

Plant Type	Tree Weed
Plant Size	As high as 20 feet
Flower Size	Small
Flower Timing	Spring
Flower Color	Yellow
Leaf Shape	Oval
Leaf Color	Silver-Gray
Growth Rate	Quickly
Temperature Requirements	Hardy in different climates
Invasive	Yes

3. Tree of Heaven (Ailanthus Altissima)

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Ailanthus altassima (the Tree of Heaven) is considered a weed in Pennsylvania due to its aggressive and invasive growth. It can disrupt native ecosystems.

This tree can reach up to 80 feet tall and is known for its large compound leaves and unique smell that resembles burnt peanut butter.

It is best to remove the entire root system, or use a herbicide that has been formulated specifically for woody plants.

Plant type	Deciduous trees
Plant size	As tall as 80 feet
Flower size	Large clusters
Flower timing	Spring and summer
Flower color	Yellow-green
Leaf color	Dark green
Leaf shape	Compound leaves up to 3 feet in length
Growth Rate	Fast
Temperature requirements	Adaptable to different climates
Invasive or Not	Yes, it is invasive

4. Black Locust (Robinia Pseudoacacia)

Image by and Credit to: Robert Flogaus-Faust

Black Locust is an invasive plant native to the U.S., which is known by its scientific name, Robinia pseudoacacia.

The distinctive bark is reddish black. Long pinnate leaves are arranged in clusters with seven to nineteen leaflets. In late spring, fragrant white flowers bloom.

To prevent regrowth, uproot and cut the roots if necessary.

Plant Type	Woody, fast-growing weed tree
Plant Size	Height: 30 to 50 feet
Flower Size	Clusters of 4 to 8 inch long
Flower Timing	Late Spring
Flower Color	White
Leaf Color	Green
Leaf Shape	Leaves arranged in clusters of 7-19 feathery leaflets.
Growth Rate	Rapid, often invasive
Temperature requirements	Adaptable to a variety of conditions
Invasive	Yes

5. Yellow Bells (Tecoma Stans)

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Yellow Bells (Tecoma Stans) is often referred to as a weed due to its rapid rate of growth and strong root system. It’s also known to be difficult to eradicate.

To identify this tree, you need to notice its distinctive compound leaf that changes from green with a border all the way through to yellow when it matures.

The removal of this tree requires a combination of uprooting the tree and applying herbicides that are targeted at woody plants.

Plant type	Hybrid polar tree
Plant size	The plant can reach a height of 30 feet
Flower size	Small
Flower timing	Spring
Flower color	Yellowish-green
Leaf color	As they mature, the green with yellow border turns completely yellow.
Leaf shape	Compound
Growth Rate	Fast
Temperature requirements	Adaptable to wide temperature ranges
Whether invasive or not	Yes

6. Camphor Laurel (Cinnamomum Camphora)

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The Camphor Laurel, Cinnamomum Camphora is a weed due to its invasiveness and rapid growth. This can cause forest destruction.

Look for glossy, dark-green evergreen leaves that are on top and whitish beneath.

A professional is best to remove it due to its large size. Small seedlings, however, can be removed by hand or treated with an herbicide.

Plant Type	Evergreen tree
Plant Size	Maximum 30m
Flower Size	Small
Flower Timing	Spring
Flower Color	White
Leaf Color	Dark green (above), Whitish
Leaf Shape	Oval, Three Vein
Growth Rate	Rapid
Temperature Requirement	Hardy in Zones 9-11
Invasive or not	Yes,

7. Chinese Celtis (Celtis Sinensis)

Image by and Credit to: Krzysztof Golik

Chinese Celtis is an invasive tree that grows rapidly and resists most herbicides. It poses a serious threat to backyard ecosystems because of its rapid growth.

Native of China, but found globally is recognizable by its alternative leaf structure, including serrate or dentate expressions, and distinct small green flowers that blossom into white when they mature.

It is best to remove it by pulling persistently, as the plant is resistant to many herbicides.

Plant Type	Weed-like Tree
Plant Size	Massive (up 60 feet)
Flower Size	Small
Flower Timing	Spring
Flower Color	White blossoms after a green start
Leaf Color	Green
Leaf Shape	Alternative arrangements (serrate or dentate)
Growth Rate	Rapid (Can colonize in two seasons).
Temperature Requirements	The Thrive in All Temperatures
Invasive or Not	Highly Invasive

8. Mysore Thorn (Caesalpinia Decapetala)

Image by and Credit to: Dinesh Valke

Mysore Thorn is scientifically known as Caesalpinia Decapetala. It’s a tree that is considered a weed because of its rapid growth and invasiveness.

The glossy leaves with large, yellow flowers and a lot of thorns are the most distinguishing features. Apply a tree-stump killer or arborist paint to minimize the chances of regrowth.

It is important to remove Mysore Thorn with diligence and assertiveness, but be careful not to allow it to overpower your landscaping.

Plant Feature	Mysore Thorn Range
Plant Type	Flowering, thorny bushes
Plant Size	As high as 32 feet
Flower Size	Small
Flower Timing	Spring to Autumn
Flower Color	Yellow
Leaf Color	Glossy Green
Leaf Shape	Fern-like
Growth Rate	Fast
Temperature Requirements	Tolerant of a wide range
Invasive or not	Highly Invasive

9. Cockspur Coral Tree (Erythrina Crista Galli)

Image by and Credit to: Zeynel Cebeci

Cockspur Coral Trees (Erythrina Crista-Galli) are weed trees due to their aggressive growth. They displace native species within an ecosystem. The thorny branch, bright red flower, and broad, scalloped leaves can all be used to identify it.

It is best to remove the Cockspur Coral Tree by cutting it to the base. Applying an herbicide that kills trees to the new wound will prevent the tree from growing back.

Plant Type	Deciduous Tree
Plant Size	Height up to 32 feet
Flower Size	The Large
Flower Timing	Blooms in Summer
Flower Color	Bright Red
Leaf Color	Green
Leaf Shape	Broad Scalloped
Growth Rate	Rapid
Temperature Requirements	Prefers Temperate and Warm Climates
Invasive or not	When it is out of its natural range, this tree can be considered an invasive species.

10. Golden Wreath Wattle (Acacia Saligna)

Image by and Credit to: Zeynel Cebeci

Golden Wreath Wattle is usually classified as a weed due to its rapid growth and ability to overwhelm native species.

Look for the clusters of golden-yellow flowers and distinctive sickle-shaped leaf shapes. Also, sharply pointed stipules are a good way to identify it. You should uproot the whole plant, not leaving any roots behind.

Plant Type	Small Trees or Shrubs
Plant Size	From 6 to 19 feet
Flower Size	Small
Flower Timing	From Late Winter to Summer
Flower Color	Golden-yellow
Leaf Color	Light Green
Leaf Shape	Sickle-shaped
Growth Rate	Fast
Temperature Requirements	Subtropical to Warm Temperate
Invasive or not	Yes,

How to Eliminate Weed Trees

Let’s look at some strategies to identify and eliminate weed trees in your garden.

• Use a Chemical Spray to Kill Weeds
• Apply a mulch layer around the weed trees
• Plants that are similar to the weed tree can be planted around it
• Label and identify the weed tree
• Rake the seeds out with a rake
• Cover the weeds with soil
• Get rid of the weeds

Use a Chemical Spray to Eliminate Weeds

By penetrating and killing the root system of the plant, a chemical spray can be used to effectively remove weed trees.

This tactic prevents the regrowth and growth of these nuisance plants. This prevents seedling regrowth, which promotes a healthier garden ecosystem.

Use Mulch to the Weed Tree

By preventing the weed tree from gaining access to sunlight and nutrients, mulch can help control and remove it. This will inhibit its growth.

Mulch is also a physical barrier that prevents weed seedlings establishing, and allowing them to become invasive.

Plant Other Kinds of Plants Around the Weed Tree

By planting other plants around weed trees, you can create competition for resources and stifle their growth. Certain plants release chemicals into the soil that inhibit weed tree growth. This helps to control the plant and remove it.

Inspect the Weed Tree and Identify It

Identification and labeling of weed trees is crucial for eliminating and controlling this invasive species. This allows for effective herbicide use and targeted removal of weed trees, resulting in a more balanced and healthy ecosystem.

Get Rid Of the Seeds

By preventing the seeds from germinating, and developing into new weeds trees, raking away the seeds is a great way to control and remove weed trees.

This preemptive measure is highly effective in cutting the life cycle of weeds right at the start. This will result in a garden that is easier to manage and free of weeds.

Cover the Weed Trees With Some Dirt

By covering weed trees in soil, you effectively deny them the necessary sunlight. This will eventually kill them by preventing their ability to photosynthesize.

It also acts as a barrier to prevent the spread of weed seed in the surrounding area. This will control the growth of weed trees.

Do Some Regular Weeding

By removing weeds quickly, you can help manage weed trees. This is because they are less likely to take root and grow into bigger, more difficult-to-control weeds.

Furthermore, regular weeding will reduce the competition for resources and promote the growth of healthy plants in your garden.

Conclusion

It’s not difficult to protect your outdoor area from the threat of tree-like weeds. You are now equipped with the knowledge from this article to recognize and control these master disguises. Assuring that your garden is lush, healthy and free of weeds. Take on these invasive species and reclaim the green space you once had!

Frequently Asked Questions

Here are some common questions regarding trees that are weeds.

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